Substrate cleaning device and substrate cleaning method

ABSTRACT

A substrate cleaning device includes: a pressing member that cleans a substrate by contacting the substrate; a load measurement unit that measures a pressing load of the cleaning member; and a control unit that repeats an operation of comparing the measurement value of the load measurement unit with the setting load, changing the pressing amount of the cleaning member by a first movement amount so that a difference value decreases, when the difference value is larger than a first threshold value and equal to or smaller than a second threshold value, and changing the pressing amount of the cleaning member by a second movement amount larger than the first movement amount so that the difference value decreases, when the difference value is larger than the second threshold value, until the difference value becomes equal to or smaller than the first threshold value.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. Patent Application No.17/489,277, filed on Sep. 29, 2021, which is a continuation of U.S.Patent Application No. 16/503,868, filed on Jul. 5, 2019, now issued asU.S. Patent No. 11,164,757, which claims the benefit of JapanesePriority Patent Application JP 2018-129086, filed on Jul. 6, 2018, theentire contents of which are incorporated herein by reference.

FIELD

The present technology relates to a substrate cleaning device and asubstrate cleaning method.

BACKGROUND AND SUMMARY

At the present time, with the miniaturization of a semiconductor device,processing of a substrate having a fine structure (a substrate on whichvarious material films having different physical properties are formed)is performed. For example, in a damascene wiring formation step offilling a wiring groove formed in the substrate with a metal, the excessmetal is polished and removed by a substrate polishing device (CMPdevice) after damascene wiring formation, and the various material films(a metal film, a barrier film, an insulating film, and the like) havingthe different physical properties are formed on a surface of thesubstrate. On the surface of the substrate, there are slurry residue andmetal polishing waste (Cu polishing waste and the like) used in CMPpolishing. For this reason, when the surface of substrate is notsufficiently cleaned, such as when the surface of the substrate iscomplicated and cleaning is difficult, leaks and adhesion defects occurdue to an influence of the residue and the like, which may result in adecrease in reliability. Therefore, in the CMP device for polishing thesemiconductor substrate, roll member scrub cleaning and pen member scrubcleaning are performed in a cleaning step after polishing.

For the roll member scrub cleaning, technology for installing a loadcell measuring a pressing load of a roll member between a lift armmoving upward and downward according to driving of an air cylinder and aroll member holder and performing feedback control on the pressing loadof the roll member via a control device of the air cylinder on the basisof a measurement value of the load cell is known (refer to JP 2014-38983A).

Incidentally, in recent years, since a substrate thickness decreases ora substrate material changes, further improvement in the accuracy of thepressing load for the substrate is required.

Accordingly, it is desirable to provide a substrate cleaning device anda substrate cleaning method capable of improving accuracy of a pressingload.

A substrate cleaning device according to an embodiment includes: acleaning member that cleans a substrate by contacting the substrate; amember rotation unit that rotates the cleaning member; a member driveunit that presses the cleaning member against the substrate; a loadmeasurement unit that measures a pressing load of the cleaning member;and a control unit that controls a pressing amount of the cleaningmember by the member drive unit, on the basis of a measurement value ofthe load measurement unit, so that the pressing load of the cleaningmember becomes a setting load, wherein the control unit repeats anoperation of comparing the measurement value of the load measurementunit with the setting load, changing the pressing amount of the cleaningmember by a first movement amount so that a difference value decreases,when the difference value is larger than a first threshold value andequal to or smaller than a second threshold value, and changing thepressing amount of the cleaning member by a second movement amountlarger than the first movement amount so that the difference valuedecreases, when the difference value is larger than the second thresholdvalue, until the difference value becomes equal to or smaller than thefirst threshold value.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view showing an example of an entire configuration of asubstrate processing apparatus according to an embodiment;

FIG. 2 is a perspective view showing a substrate cleaning deviceaccording to a first embodiment;

FIG. 3 is a diagram showing a schematic configuration of the substratecleaning device according to the first embodiment;

FIG. 4 is a flowchart illustrating an example of a substrate cleaningmethod by the substrate cleaning device according to the firstembodiment;

FIG. 5 is a flowchart illustrating a step of controlling a pressingamount of a cleaning member on the basis of a measurement value of apressing load;

FIG. 6 is a flowchart illustrating a step of calculating a pressingamount of the cleaning member corresponding to a setting load;

FIG. 7A is a diagram showing an example of master data;

FIG. 7B is a diagram showing an example of measurement data;

FIG. 7C is a diagram showing an example of data for movement amountcalculation;

FIG. 8 is a perspective view showing a substrate cleaning deviceaccording to a second embodiment;

FIG. 9 is a diagram showing a schematic configuration of the substratecleaning device according to the second embodiment;

FIG. 10 is a flowchart illustrating an example of a substrate cleaningmethod by the substrate cleaning device according to the secondembodiment;

FIG. 11 is a flowchart illustrating a step of contacting a firstcleaning member and a second cleaning member with a substrate;

FIGS. 12A to 12C are diagrams illustrating a step of contacting thefirst cleaning member and the second cleaning member with the substrate;

FIG. 13 is a perspective view showing a substrate cleaning deviceaccording to a first modification of the first embodiment; and

FIG. 14 is a perspective view showing a substrate cleaning deviceaccording to a second modification of the first embodiment.

DETAILED DESCRIPTION OF NON-LIMITING EXAMPLE EMBODIMENTS

A substrate cleaning device according to a first aspect of an embodimentincludes: a cleaning member that cleans a substrate by contacting thesubstrate; a member rotation unit that rotates the cleaning member; amember drive unit that presses the cleaning member against thesubstrate; a load measurement unit that measures a pressing load of thecleaning member; and a control unit that controls a pressing amount ofthe cleaning member by the member drive unit, on the basis of ameasurement value of the load measurement unit, so that the pressingload of the cleaning member becomes a setting load, wherein the controlunit repeats an operation of comparing the measurement value of the loadmeasurement unit with the setting load, changing the pressing amount ofthe cleaning member by a first movement amount so that a differencevalue decreases, when the difference value is larger than a firstthreshold value and equal to or smaller than a second threshold value,and changing the pressing amount of the cleaning member by a secondmovement amount larger than the first movement amount so that thedifference value decreases, when the difference value is larger than thesecond threshold value, until the difference value becomes equal to orsmaller than the first threshold value.

According to the first aspect, when the difference value between themeasurement value of the load measurement unit and the setting load islarger than the first threshold value and equal to or smaller than thesecond threshold value, the control unit changes the pressing amount ofthe cleaning member by the first movement amount. However, when thedifference value is larger than the second threshold value, the controlunit changes the pressing amount of the cleaning member by the secondmovement amount larger than the first movement amount (that is, closedloop control of two steps). As a result, as compared with a method (thatis, closed loop control of one step) of changing the pressing amount ofthe cleaning member by the first movement amount even when thedifference value is larger than the second threshold value, it ispossible to shorten a time until the difference value converges to thefirst threshold value or less, which can lead to an increase in thenumber of substrates processed per unit time (wph; wafer per hour).Further, as compared with a method (that is, closed loop control of onestep) of changing the pressing amount of the cleaning member by thesecond movement amount even when the difference value is equal to orsmaller than the second threshold value, the pressing amount can becontrolled with high accuracy. As a result, accuracy of the pressingload can be improved.

A substrate cleaning device according to a second aspect of theembodiment includes: a cleaning member that cleans a substrate bycontacting the substrate; a member rotation unit that rotates thecleaning member; a member drive unit that presses the cleaning memberagainst the substrate; a load measurement unit that measures a pressingload of the cleaning member; and a control unit that controls a pressingamount of the cleaning member by the member drive unit, on the basis ofa measurement value of the load measurement unit, so that the pressingload of the cleaning member becomes a setting load, wherein the controlunit previously stores a correspondence relation between the pressingload and the pressing amount of the cleaning member for M (M is anatural number of 2 or more) pressing loads as master data, the controlunit acquires the correspondence relation between the pressing load andthe pressing amount of the cleaning member for N (N is a natural numbersmaller than M) pressing loads among the M pressing loads as measurementdata, on the basis of the measurement value of the load measurementunit, the control unit corrects each of pressing amounts correspondingto the M pressing loads in the master data, on the basis of themeasurement data, so that the correspondence relation between thepressing load and the pressing amount for the N pressing loads in themaster data approaches the correspondence relation between the pressingload and the pressing amount for the N pressing loads in the measurementdata, and generates data for movement amount calculation showing thecorrespondence relation between the pressing load and the pressingamount for the M pressing loads, and the control unit calculates thepressing amount of the cleaning member corresponding to the settingload, on the basis of the correspondence relation between the pressingload and the pressing amount in the data for movement amountcalculation.

According to the second aspect, the control unit corrects thecorrespondence relation between the pressing load and the pressingamount in the master data, on the basis of the measurement data, andcalculates the pressing amount of the cleaning member, on the basis ofthe correspondence relation (= data for movement amount calculation)after correction. Therefore, the control unit can determine the pressingamount with high accuracy as compared with the case where the pressingamount of the cleaning member is calculated on the basis of thecorrespondence relation (= master data) before correction. As a result,accuracy of the pressing load can be improved.

According to a substrate cleaning device according to a third aspect ofthe embodiment, in the substrate cleaning device according to the firstor second aspect, the cleaning member is any one member of the groupconsisting of a roll cleaning member, a pencil cleaning member, and abuff cleaning/polishing member.

According to a substrate cleaning device according to a fourth aspect ofthe embodiment, in the substrate cleaning device according to any one ofthe first to third aspects, the member drive unit is an electricactuator.

According to the fourth aspect, the pressing amount of the cleaningmember can be controlled with high accuracy as compared with the casewhere an air cylinder is adopted as the member drive unit. As a result,accuracy of the pressing load can be further improved.

A substrate cleaning device according to a fifth aspect of theembodiment includes: a first cleaning member that cleans a first surfaceof a substrate by contacting the first surface of the substrate; a firstmember rotation unit that rotates the first cleaning member; a firstmember drive unit that presses the first cleaning member against thefirst surface of the substrate; a first load measurement unit thatmeasures a pressing load of the first cleaning member; a second cleaningmember that cleans a second surface of the substrate by contacting thesecond surface of the substrate; a second member rotation unit thatrotates the second cleaning member; a second member drive unit thatpresses the second cleaning member against the second surface of thesubstrate; a second load measurement unit that measures a pressing loadof the second cleaning member; and a control unit that controls apressing amount of the first cleaning member by the first member driveunit and a pressing amount of the second cleaning member by the secondmember drive unit, on the basis of a measurement value of the first loadmeasurement unit and a measurement value of the second load measurementunit, so that the pressing load of the first cleaning member becomes afirst setting load and the pressing load of the second cleaning memberbecomes a second setting load, wherein the control unit is configured toexecute a first step of controlling the first member drive unit and thesecond member drive unit so that the first cleaning member moves at afirst movement speed from a first initial position separated from thefirst surface of the substrate by a first distance to a first proximityposition separated from the first surface by a third distance and thesecond cleaning member moves at a second movement speed from a secondinitial position separated from the second surface of the substrate by asecond distance shorter than the first distance to a second proximityposition separated from the second surface by the third distance and asecond step of controlling the first member drive unit and the secondmember drive unit so that the first cleaning member and the secondcleaning member simultaneously start moving at a third movement speedlower than the first movement speed and simultaneously contact the firstsurface and the second surface of the substrate, respectively, and thecontrol unit is configured to determine the second movement speed of thesecond cleaning member by the second member drive unit, on the basis ofthe first movement speed of the first cleaning member by the firstmember drive unit, so that the first cleaning member disposed at thefirst initial position and the second cleaning member disposed at thesecond initial position simultaneously start the moving and the secondcleaning member reaches the second proximity position at timingidentical to timing when the first cleaning member reaches the firstproximity position, before the first step.

According to the fifth aspect, the second movement speed of the secondcleaning member disposed at the second initial position relatively closeto the substrate is determined on the basis of the first movement speedof the first cleaning member disposed at the first initial positionrelatively far from the substrate. Therefore, it is possible to shortena time required for causing the first cleaning member and the secondcleaning member to reach the first proximity position and the secondproximity position, respectively. As a result, it is possible toincrease the number of substrates processed per unit time (wph; waferper hour). Further, the first cleaning member and the second cleaningmember respectively disposed at the first proximity position and thesecond proximity position having the same distances from the substrateare moved symmetrically with respect to the substrate and the firstcleaning member and the second cleaning member are simultaneouslycontacted with the substrate. Therefore, it is possible tosimultaneously and accurately position the first cleaning member and thesecond cleaning member on the surfaces of the substrate. As a result,subsequent pressing amount control can be performed with high accuracy,and accuracy of the pressing load can be improved.

According to a substrate cleaning device according to a sixth aspect ofthe embodiment, in the substrate cleaning device according to the fifthaspect, each of the first cleaning member and the second cleaning memberis a roll cleaning member.

According to a substrate cleaning device according to a seventh aspectof the embodiment, in the substrate cleaning device according to thefifth or sixth aspect, each of the first member drive unit and thesecond member drive unit is an electric actuator.

According to the seventh aspect, the pressing amounts of the firstcleaning member and the second cleaning member can be controlled withhigh accuracy, as compared with the case where air cylinders are adoptedas the first member drive unit and the second member drive unit. As aresult, accuracy of the pressing load can be further improved.

A substrate processing apparatus according to an eighth aspect of theembodiment includes the substrate cleaning device according to any oneof the first to seventh aspects.

A substrate cleaning method according to a ninth aspect of theembodiment includes: a step of causing a member drive unit to press acleaning member against a substrate; a step of causing a loadmeasurement unit to measure a pressing load of the cleaning member; anda step of causing a control unit to control a pressing amount of thecleaning member by the member drive unit, on the basis of a measurementvalue of the load measurement unit, so that the pressing load of thecleaning member becomes a setting load, wherein, in the step ofcontrolling the pressing amount, the control unit repeats an operationof comparing the measurement value of the load measurement unit with thesetting load, changing the pressing amount of the cleaning member by afirst movement amount so that a difference value decreases, when thedifference value is larger than a first threshold value and equal to orsmaller than a second threshold value, and changing the pressing amountof the cleaning member by a second movement amount larger than the firstmovement amount so that the difference value decreases, when thedifference value is larger than the second threshold value, until thedifference value becomes equal to or smaller than the first thresholdvalue.

A substrate cleaning method according to a tenth aspect of theembodiment includes: a step of causing a control unit to calculate apressing amount of a cleaning member corresponding to a setting load; astep of causing a member drive unit to press the cleaning member againsta substrate by the calculated pressing amount; a step of causing a loadmeasurement unit to measure a pressing load of the cleaning member; anda step of causing a control unit to control the pressing amount of thecleaning member by the member drive unit, on the basis of a measurementvalue of the load measurement unit, so that the pressing load of thecleaning member becomes the setting load, wherein the control unitpreviously stores a correspondence relation between the pressing loadand the pressing amount of the cleaning member for M (M is a naturalnumber of 2 or more) pressing loads as master data, and in the step ofcalculating the pressing amount, the control unit acquires thecorrespondence relation between the pressing load and the pressingamount of the cleaning member for N (N is a natural number smaller thanM) pressing loads among the M pressing loads as measurement data, on thebasis of the measurement value of the load measurement unit, the controlunit corrects each of pressing amounts corresponding to the M pressingloads in the master data, on the basis of the measurement data, so thatthe correspondence relation between the pressing load and the pressingamount for the N pressing loads in the master data approaches thecorrespondence relation between the pressing load and the pressingamount for the N pressing loads in the measurement data, and generatesdata for movement amount calculation showing the correspondence relationbetween the pressing load and the pressing amount for the M pressingloads, and the control unit calculates the pressing amount of thecleaning member corresponding to the setting load, on the basis of thecorrespondence relation between the pressing load and the pressingamount in the data for movement amount calculation.

According to a substrate cleaning method according to an eleventh aspectof the embodiment, in the substrate cleaning method according to theninth or tenth aspect, the cleaning member is any one member of thegroup consisting of a roll cleaning member, a pencil cleaning member,and a buff cleaning/polishing member.

According to a substrate cleaning method according to a twelfth aspectof the embodiment, in the substrate cleaning method according to any oneof the ninth to eleventh aspects, the member drive unit is an electricactuator.

A substrate cleaning method according to a thirteenth aspect of theembodiment includes: a step of causing a first member drive unit tocontact a first cleaning member with a first surface of a substrate andcausing a second member drive unit to contact a second cleaning memberwith a second surface of the substrate; a step of causing the firstmember drive unit to press the first cleaning member against the firstsurface of the substrate and causing the second member drive unit topress the second cleaning member against the second surface of thesubstrate; a step of causing a first load measurement unit to measure apressing load of the first cleaning member and causing a second loadmeasurement unit to measure a pressing load of the second cleaningmember; and a step of causing a control unit to control each of apressing amount of the first cleaning member by the first member driveunit and a pressing amount of the second cleaning member by the secondmember drive unit, on the basis of a measurement value of the first loadmeasurement unit and a measurement value of the second load measurementunit, so that the pressing load of the first cleaning member becomes afirst setting load and the pressing load of the second cleaning memberbecomes a second setting load, wherein the step of contacting the firstcleaning member and the second cleaning member with the substrateincludes a first step of causing the control unit to control the firstmember drive unit and the second member drive unit so that the firstcleaning member moves at a first movement speed from a first initialposition separated from the first surface of the substrate by a firstdistance to a first proximity position separated from the first surfaceby a third distance and the second cleaning member moves at a secondmovement speed from a second initial position separated from the secondsurface of the substrate by a second distance shorter than the firstdistance to a second proximity position separated from the secondsurface by the third distance and a second step of causing the controlunit to control the first member drive unit and the second member driveunit so that the first cleaning member and the second cleaning membersimultaneously start moving at a third movement speed lower than thefirst movement speed and simultaneously contact the first surface andthe second surface of the substrate, respectively, and the control unitdetermines the second movement speed of the second cleaning member, onthe basis of the first movement speed of the first cleaning member, sothat the first cleaning member disposed at the first initial positionand the second cleaning member disposed at the second initial positionsimultaneously start the moving and the second cleaning member reachesthe second proximity position at timing identical to timing when thefirst cleaning member reaches the first proximity position, before thefirst step.

According to a substrate cleaning method according to a fourteenthaspect of the embodiment, in the substrate cleaning method according tothe thirteenth aspect, each of the first cleaning member and the secondcleaning member is a roll cleaning member.

According to a substrate cleaning method according to a fifteenth aspectof the embodiment, in the substrate cleaning method according to thethirteenth or fourteenth aspect, each of the first member drive unit andthe second member drive unit is an electric actuator.

Hereinafter, specific examples of an embodiment will be described indetail with reference to the accompanying drawings. In the followingdescription and the drawings used in the following description, the samereference numerals will be used for parts that can be configured in thesame way, and redundant descriptions will be omitted.

Substrate Processing Apparatus

FIG. 1 is a plan view showing an entire configuration of a substrateprocessing apparatus 1 according to an embodiment.

As shown in FIG. 1 , the substrate processing apparatus 1 has asubstantially rectangular housing 10 and a load port 12 on which asubstrate cassette (not shown in the drawings) for stocking a pluralityof substrates W (refer to FIG. 2 or the like) is placed. The load port12 is disposed to be adjacent to the housing 10. The load port 12 can beequipped with an open cassette, a standard manufacturing interface(SMIF) pod, or a front opening unified pod (FOUP). The SMIF pod and theFOUP are closed containers that can maintain the environment independentof an external space by accommodating the substrate cassette inside andcovering the substrate cassette with a partition wall. As the substrateW, for example, a semiconductor wafer or the like can be mentioned.

In the housing 10, a plurality of (four in an aspect shown in FIG. 1 )substrate polishing devices 14 a to 14 d, a first substrate cleaningdevice 16 a and a second substrate cleaning device 16 b for cleaning thesubstrate W after polishing, and a substrate drying device 20 for dryingthe substrate W after cleaning are accommodated. The substrate polishingdevices 14 a to 14 d are arranged along a longitudinal direction of thehousing 10, and the substrate cleaning devices 16 a and 16 b and thesubstrate drying device 20 are also arranged along the longitudinaldirection of the housing 10.

A first transfer robot 22 is disposed in a region surrounded by the loadport 12, the substrate polishing device 14 a located at the side of theload port 12, and the substrate drying device 20. Further, a transferunit 24 is disposed in parallel with the longitudinal direction of thehousing 10, between a region where the substrate polishing devices 14 ato 14 d are arranged and a region where the substrate cleaning devices16 a and 16 b and the substrate drying device 20 are arranged. The firsttransfer robot 22 receives the substrate W before polishing from theload port 12 and transfers the substrate W to the transfer unit 24 orreceives the dried substrate W extracted from the substrate dryingdevice 20 from the transfer unit 24.

A second transfer robot 26 for transferring the substrate W between thefirst substrate cleaning device 16 a and the second substrate cleaningdevice 16 b is disposed between the first substrate cleaning device 16 aand the second substrate cleaning device 16 b. Further, a third transferrobot 28 for transferring the substrate W between the second substratecleaning device 16 b and the substrate drying device 20 is disposedbetween the second substrate cleaning device 16 b and the substratedrying device 20.

Further, the substrate processing apparatus 1 is provided with a controlpanel 30 for controlling the movement of each of the devices 14 a to 14d, 16 a, 16 b, 22, 24, 26, and 28. In the aspect shown in FIG. 1 ,although the control panel 30 is disposed inside the housing 10, thecontrol panel 30 is not limited thereto and may be disposed outside thehousing 10.

As the first substrate cleaning device 16 a and/or the second substratecleaning device 16 b, a roll cleaning device (a substrate cleaningdevice 16 according to a first embodiment or a substrate cleaning device16′ according to a second embodiment to be described later) thatcontacts a roll cleaning member extending linearly over substantially anentire length of a diameter of the substrate W with a surface of thesubstrate W in the presence of a cleaning liquid and scrub-cleans thesurface of the substrate W while rotating the roll cleaning member maybe used, a pencil cleaning device (substrate cleaning device 16according to a first modification of the first embodiment to bedescribed later) that contacts a columnar pencil cleaning memberextending in a vertical direction with the surface of the substrate W inthe presence of the cleaning liquid, moves the pencil cleaning member inone direction parallel to the surface of the substrate W while rotatingthe pencil cleaning member, and scrub-cleans the surface of thesubstrate W may be used, a buff cleaning/polishing device (substratecleaning device 16 according to a second modification of the firstembodiment to be described later) that contacts a buffcleaning/polishing member with a rotation axis extending in a verticaldirection with the surface of the substrate W in the presence of thecleaning liquid, moves the buff cleaning/polishing member in onedirection parallel to the surface of the substrate W while rotating thebuff cleaning/polishing member, and scrub-cleans and polishes thesurface of the substrate W may be used, and a two-fluid jet cleaningdevice that cleans the surface of the substrate W by a two-fluid jet maybe used. Further, as the first substrate cleaning device 16 a and/or thesecond substrate cleaning device 16 b, any combination of two or moredevices of the roll cleaning device, the pencil cleaning device, thebuff cleaning/polishing device, and the two-fluid jet cleaning devicemay be used.

The cleaning liquid includes a rinse liquid such as pure water (DIW) anda chemical liquid such as ammonia hydrogen peroxide (SC1), hydrochloricacid hydrogen peroxide (SC2), sulfuric acid hydrogen peroxide (SPM),sulfuric acid hydration, or hydrofluoric acid. Unless otherwise noted inthe present embodiment, the cleaning liquid means either the rinseliquid or the chemical liquid.

As the substrate drying device 20, a spin drying device that jets IPAvapor from an injection nozzle moving in one direction parallel to thesurface of the substrate W toward the rotating substrate W to dry thesubstrate W and rotates the substrate W at high speed to dry thesubstrate W by a centrifugal force may be used.

Substrate Cleaning Device According to First Embodiment

Next, a substrate cleaning device 16 according to the first embodimentwill be described. FIG. 2 is a perspective view showing the substratecleaning device 16 according to the first embodiment and FIG. 3 is adiagram showing a schematic configuration of the substrate cleaningdevice 16 according to the first embodiment. The substrate cleaningdevice 16 according to the first embodiment may be used as the firstsubstrate cleaning device 16 a and/or the second substrate cleaningdevice 16 b in the substrate processing apparatus 1 described above.

As shown in FIGS. 2 and 3 , the substrate cleaning device 16 has acleaning member 46 that cleans a substrate W by contacting the substrateW, a member rotation unit 96 that rotates the cleaning member 46, amember drive unit 56 that presses the cleaning member 46 against thesubstrate W, a load measurement unit 54 that measures a pressing load ofthe cleaning member 46, and a control unit 90 that controls a pressingamount of the cleaning member 46 by the member drive unit 56, on thebasis of a measurement value of load measurement unit 54, so that thepressing load of the cleaning member 46 becomes a setting load.

In the examples shown in FIGS. 2 and 3 , although the cleaning member 46is a roll cleaning member (roll sponge) extending in a columnar shapeand a long shape and made of PVA, for example, the cleaning member 46 isnot limited thereto and may be a pencil cleaning member (refer to FIG.13 ) with a columnar shape extending in a vertical direction or a buffcleaning/polishing member (refer to FIG. 14 ) with a rotation axisextending in the vertical direction.

As shown in FIG. 2 , the substrate cleaning device 16 is provided with asubstrate rotation mechanism 40 for supporting and rotating thesubstrate W, a member holder 42 disposed liftably above the substrate Wsupported and rotated by the substrate rotation mechanism 40, and acleaning liquid supply unit 50 for supplying a cleaning liquid to asurface of the substrate W, and the cleaning member 46 is supportedrotatably by the member holder 42.

In the example shown in the drawings, the substrate rotation mechanism40 is a plurality of horizontally movable (four in the example shown inthe drawings) spindles that support a circumferential part of thesubstrate W and horizontally rotate the substrate W. However, thesubstrate rotation mechanism 40 is not limited thereto and may berotatable chucks. An arrow E of FIG. 2 indicates a rotation direction ofthe substrate W by the substrate rotation mechanism 40.

As shown in FIG. 3 , the member rotation unit 96 is fixed to one endside of the member holder 42 in the longitudinal direction. As themember rotation unit 96, for example, a motor is used. The memberrotation unit 96 is driven, so that the cleaning member 46 is rotatedabout a center axis parallel to the surface of the substrate W. An arrowF1 of FIG. 2 indicates a rotation direction of the cleaning member 46 bythe member rotation unit 96.

In the examples shown in FIGS. 2 and 3 , a recess 42 a is formedsubstantially at the center of the member holder 42 along thelongitudinal direction, and the load measurement unit 54 is disposed inthe recess 42 a and is fixed to the member holder 42. As the loadmeasurement unit 54, for example, a load cell is used.

As the member drive unit 56, for example, an electric actuator is used.The electric actuator may be a ball screw type electric actuator, may bea rack pinion type electric actuator, or may be a direct driven typeelectric actuator (linear motor).

In the example shown in the drawings, the substrate cleaning device 16is provided with a lift shaft 57 lifted by driving of the member driveunit 56 and extending in a vertical direction and a lift arm 58 having abase end connected to an upper end of the lift shaft 57 and extending ina horizontal direction, and the member holder 42 is connected to a tipof the lift arm 58 via the load measurement unit 54. Further, a tiltmechanism 70 for tilting the member holder 42 is provided between theload measurement unit 54 and the tip of the lift arm 58. The memberdrive unit 56 is driven, so that the member holder 42 is liftedintegrally with the lift shaft 57 and the lift arm 58 above thesubstrate W supported and rotated by the substrate rotation mechanism40.

The control unit 90 has a programmable logic controller (PLC) thatreceives an output signal of the load measurement unit 54 and a motorcontroller that supplies electric pulses of a predetermined number ofpulses to the member drive unit 56, according to an instruction from thePLC. At least a part of the control unit 90 may be provided in thecontrol panel 30 described above. Further, in the control unit 90, atarget value of the pressing load of the cleaning member 46 is stored inadvance as a “setting load”, on the basis of an input from a user to thecontrol panel 30.

By adjusting the number of pulses of the electric pulses supplied fromthe control unit 90 to the member drive unit 56, a movement amount (apressing amount when the cleaning member 46 contacts the surface of thesubstrate W) of the member holder 42 in the vertical direction can beadjusted with high accuracy.

The member holder 42 is connected to the tip of the lift arm 58 via theload measurement unit 54. In a state where the cleaning member 46 doesnot contact the substrate W, a weight of the member holder 42 ismeasured as a tensile load by the load measurement unit 54. At the timeof cleaning the substrate W, if the member holder 42 is moved downwardby the member drive unit 56 and the cleaning member 46 contacts thesubstrate W, the tensile load applied to the load measurement unit 54decreases according to a deformation amount of the cleaning member 46and a decreased amount of the tensile load is matched with the pressingload applied to the substrate W by the cleaning member 46.

Thereby, the pressing load applied to the substrate W by the cleaningmember 46 at the time of cleaning the substrate W is measured by theload measurement unit 54 by the decreased tensile load. The control unit90 calculates a necessary movement amount of the cleaning member 46, onthe basis of a measurement value of the load measurement unit 54, sothat the pressing load of the cleaning member 46 becomes the settingload, and supplies the electric pulses of the number of pulsescorresponding to the calculated movement amount to the member drive unit56. As a result, the pressing amount of the cleaning member 46 by themember drive unit 56 is adjusted, and the pressing load for thesubstrate W is adjusted according to the deformation amount of thecleaning member 46.

In the present embodiment, at the time of cleaning the substrate W, thecontrol unit 90 adjusts the pressing load of the cleaning member 46 byclosed loop control of a plurality of steps (for example, two steps).That is, at the time of cleaning the substrate, the control unit 90compares the measurement value of the load measurement unit 54 with thesetting load. When a difference value is larger than a first thresholdvalue (for example, 0.1 N) and equal to or smaller than a secondthreshold value (for example, 1.5 N), the control unit 90 changes(adjusts) the pressing amount of the cleaning member 46 by a firstmovement amount (for example, 0.01 mm) so that the difference valuedecreases, and when the difference value is larger than the secondthreshold value (for example, 1.5 N), the control unit 90 changes(adjusts) the pressing amount of the cleaning member 46 by a secondmovement amount (for example, 0.05 mm) larger than the first movementamount (for example, 0.01 mm) so that the difference value decreases.The control unit 90 repeats the above operation until the differencevalue becomes equal to or smaller than the first threshold value (0.1N). As described above, when the pressing load of the cleaning member 46is adjusted, the control unit 90 performs the closed loop control of theplurality of steps (for example, the two steps). As a result, it ispossible to shorten a time required for adjusting the pressing load, ascompared with the case of performing the closed loop control of onestep.

Further, in the present embodiment, referring to FIG. 7A, the controlunit 90 previously stores a correspondence relation between the pressingload and the pressing amount of the cleaning member 46 for M (6 in theexample shown in the drawing) pressing loads (= 2, 4, 6, 8, 10, and 12N) as master data in a storage medium (memory). The master data may bevalues obtained by previously measuring the correspondence relationbetween the pressing load and the pressing amount of the cleaning member46 as a guide using a dummy substrate in a substrate cleaning devicemaker or the like, for example.

Furthermore, referring to FIG. 7B, the control unit 90 acquires thecorrespondence relation between the pressing load and the pressingamount of the cleaning member 46 for N (three in the example shown inthe drawing) pressing loads (= 2, 6, and 10 N) among the M pressingloads as measurement data, on the basis of the measurement value of theload measurement unit 54, before cleaning the substrate W. The controlunit 90 stores the acquired measurement data in the storage medium(memory).

In addition, the control unit 90 corrects each of the pressing amountscorresponding to the M pressing loads (= 2, 4, 6, 8, 10, and 12 N) inthe master data, on the basis of the measurement data, so that thecorrespondence relation between the pressing load and the pressingamount for the N pressing loads (= 2, 6, and 10 N) in the master data(refer to FIG. 7A) approaches the correspondence relation between thepressing load and the pressing amount for the N pressing loads (= 2, 6,and 10 N) in the measurement data (refer to FIG. 7B), and generates datafor movement amount calculation (refer to FIG. 7C) showing thecorrespondence relation between the pressing load and the pressingamount for the M pressing loads (= 2, 4, 6, 8, 10, and 12 N).Specifically, in the examples shown in FIGS. 7A to 7C, for each of thepressing loads of 2, 6, and 10 N, the pressing amount in the measurementdata is 50 µm larger than the pressing amount in the master data.Therefore, the control unit 90 generates a numerical value obtained byadding 50 µm to the pressing amount in the master data for each of thepressing loads of 2, 4, 6, 8, 10, and 12 N as data for movement amountcalculation. The control unit 90 stores the generated data for movementamount calculation in the storage medium (memory).

In addition, at the time of cleaning the substrate W, the control unit90 calculates the pressing amount of the cleaning member 46corresponding to the setting load, on the basis of the correspondencerelation between the pressing load and the pressing amount in thegenerated data for movement amount calculation (refer to FIG. 7C).Specifically, for example, when the setting load is 8 N, instead ofcalculating the pressing amount necessary for realizing the setting loadas 800 µm by referring to the master data (FIG. 7A), the control unit 90calculates the pressing amount as 850 µm by referring to the data formovement amount calculation (FIG. 7C). As a result, the control unit 90can calculate the pressing amount of the cleaning member 46 with highaccuracy, as compared with the case where the pressing amount iscalculated on the basis of the master data before correction.

Next, an example of a substrate cleaning method by the substratecleaning device 16 having the above configuration will be described.FIG. 4 is a flowchart illustrating an example of the substrate cleaningmethod. FIG. 5 is a flowchart illustrating a step of controlling thepressing amount of the cleaning member 46 on the basis of themeasurement value of the pressing load. FIG. 6 is a flowchartillustrating a step of calculating the pressing amount of the cleaningmember 46 corresponding to the setting load.

As shown in FIG. 4 , first, if the user inputs the setting load via thecontrol panel 30, the control unit 90 calculates the pressing amount ofthe cleaning member 46 corresponding to the input setting load (stepS10).

Specifically, for example, as shown in FIG. 6 , when the control unit 90previously stores a correspondence relation between the pressing loadand the pressing amount of the cleaning member 46 for the M (6 in theexample shown in the drawing) pressing loads (= 2, 4, 6, 8, 10, and 12N) as the master data in the storage medium (memory) by referring toFIG. 7A, the control unit 90 acquires the correspondence relationbetween the pressing load and the pressing amount of the cleaning member46 with respect to the actual substrate W for N (3 in the example shownin the drawing) pressing loads (= 2, 6, and 10 N) among the M pressingloads as measurement data, on the basis of the measurement value of theload measurement unit 54, by referring to FIG. 7B (step S11). Inaddition, the control unit 90 stores the acquired measurement data inthe storage medium (memory).

Next, the control unit 90 corrects each of the pressing amountscorresponding to the M pressing loads (= 2, 4, 6, 8, 10, and 12 N) inthe master data, on the basis of the measurement data, so that thecorrespondence relation between the pressing load and the pressingamount for the N pressing loads (= 2, 6, and 10 N) in the master data(refer to FIG. 7A) approaches the correspondence relation between thepressing load and the pressing amount for the N pressing loads (= 2, 6,and 10 N) in the measurement data (refer to FIG. 7B), and generates datafor movement amount calculation (refer to FIG. 7C) showing thecorrespondence relation between the pressing load and the pressingamount for the M pressing loads (= 2, 4, 6, 8, 10, and 12 N) (step S12).The control unit 90 stores the generated data for movement amountcalculation in the storage medium (memory).

In addition, the control unit 90 calculates the pressing amount of thecleaning member 46 corresponding to the setting load input by the user,on the basis of the correspondence relation between the pressing loadand the pressing amount in the generated data for movement amountcalculation (refer to FIG. 7C) (step S13). As a result, it is possibleto calculate the pressing amount of the cleaning member 46 with highaccuracy in accordance with the actual substrate W, as compared with thecase where the pressing amount is calculated on the basis of the masterdata before correction.

As shown in FIG. 2 , after calculating the pressing amount of thecleaning member 46 corresponding to the setting load, the control unit90 supplies electric pulses of a predetermined number of pulses to themember drive unit 56, moves downward the cleaning member 46 by drivingof the member drive unit 56, and contacts the cleaning member 46 withthe surface of the substrate W (step S20). At this time, the cleaningmember 46 only contacts the surface of the substrate W, the deformationamount of the cleaning member 46 is zero, and the pressing load of thecleaning member 46 for the substrate W is also zero.

Next, the control unit 90 supplies the electric pulses of the number ofpulses according to the pressing amount calculated in step S10 to themember drive unit 56 and presses the cleaning member 46 against thesurface of the substrate W by the calculated pressing amount by drivingof the member drive unit 56 (step S30).

The load measurement unit 54 measures the pressing load of the cleaningmember 46 for the substrate W (step S40).

In addition, the control unit 90 controls the pressing amount of thecleaning member 46 by the member drive unit 56 by the closed loopcontrol, on the basis of the measurement value of the load measurementunit 54, so that the pressing load of the cleaning member 46 becomes thesetting load input by the user (step S50).

Specifically, for example, as shown in FIG. 5 , the control unit 90acquires the measurement value of the pressing load from the loadmeasurement unit 54 (step S51) and compares the acquired measurementvalue of the pressing load with the setting load (step S52).

Then, the control unit 90 determines whether or not a difference valueΔF between the measurement value of the pressing load and the settingload is equal to or smaller than the second threshold value (forexample, 1.5 N) previously stored in the control unit 90 (step S53).

Then, when the difference value is larger than the second thresholdvalue (ΔF > 1.5 N), the control unit 90 supplies the electric pulses ofthe number of pulses corresponding to the predetermined second movementamount (for example, 0.05 mm) to the member drive unit 56 and changes(adjusts) the pressing amount of the cleaning member 46 by the secondmovement amount (0.05 mm) by driving of the member drive unit 56 (stepS55). Then, the processing is repeated from step S51 (closed loopcontrol of the first step).

On the other hand, when the difference value is equal to or smaller thanthe second threshold value (ΔF ≤ 1.5 N) (step S53: YES), the controlunit 90 determines whether the difference value ΔF between themeasurement value of the pressing load and the setting load is equal toor smaller than the first threshold value (for example, 0.1 N) smallerthan the second threshold value previously stored in the control unit 90(step S54).

Then, when the difference value is larger than the first threshold value(ΔF > 0.1 N), the control unit 90 supplies the electric pulses of thenumber of pulses corresponding to the first movement amount (forexample, 0.01 mm) smaller than the predetermined second movement amountto the member drive unit 56 and changes (adjusts) the pressing amount ofthe cleaning member 46 by the first movement amount (0.01 mm) by drivingof the member drive unit 56 (step S56). Then, the processing is repeatedfrom step S51 (closed loop control of the second step).

On the other hand, when the difference value is equal to or smaller thanthe first threshold value (ΔF ≤ 0.1 N) (step S54: YES), the processingof step S50 ends. As a result, the pressing load of the cleaning member46 is adjusted with high accuracy so as to have substantially the samevalue as the setting load input by the user.

According to the present embodiment described above, when the differencevalue between the measurement value of the load measurement unit 54 andthe setting load is larger than the first threshold value and equal toor smaller than the second threshold value, the control unit 90 changesthe pressing amount of the cleaning member 46 by the first movementamount (that is, finely adjusts the pressing amount when the differencevalue is small). However, when the difference value is larger than thesecond threshold value, the control unit 90 changes the pressing amountof the cleaning member 46 by the second movement amount larger than thefirst movement amount (that is, roughly adjusts the pressing amount whenthe difference value is large). As a result, as compared with the methodof changing the pressing amount of the cleaning member 46 by the firstmovement amount even when the difference value is larger than the secondthreshold value (that is, finely adjusting the pressing amount even whenthe difference value is large), it is possible to shorten a time untilthe difference value converges to the first threshold value or less,which can lead to an increase in the number of substrates processed perunit time (wph; wafer per hour). Further, as compared with the method ofchanging the pressing amount of the cleaning member by the secondmovement amount even when the difference value is equal to or smallerthan the second threshold value (that is, roughly adjusting the pressingamount even when the difference value is small), the pressing amount canbe controlled with high accuracy. As a result, accuracy of the pressingload can be improved.

Further, according to the present embodiment, the control unit 90corrects the correspondence relation between the pressing load and thepressing amount in the master data (refer to FIG. 7A), on the basis ofthe measurement data (refer to FIG. 7B), and calculates the pressingamount of the cleaning member 46, on the basis of the data for movementamount calculation (refer to FIG. 7C) to be the correspondence relationafter correction. Therefore, the control unit 90 can determine thepressing amount with high accuracy as compared with the case where thepressing amount of the cleaning member 46 is calculated on the basis ofthe correspondence relation (= master data) before correction. As aresult, accuracy of the pressing load can be improved.

Further, according to the present embodiment, since the member driveunit 56 is the electric actuator, the pressing amount of the cleaningmember 46 can be controlled with high accuracy as compared with the casewhere an air cylinder is adopted as the member drive unit 56. As aresult, accuracy of the pressing load can be further improved.

Substrate Cleaning Device According to Second Embodiment

Next, a substrate cleaning device 16′ according to a second embodimentwill be described. FIG. 8 is a perspective view showing the substratecleaning device 16′ according to the second embodiment and FIG. 9 is adiagram showing a schematic configuration of the substrate cleaningdevice 16′ according to the second embodiment. The substrate cleaningdevice 16′ according to the second embodiment may be used as a firstsubstrate cleaning device 16 a and/or a second substrate cleaning device16 b in the substrate processing apparatus 1 described above.

As shown in FIGS. 8 and 9 , in addition to a configuration of asubstrate cleaning device 16 according to the first embodiment describedabove, the substrate cleaning device 16′ according to the secondembodiment further has a second cleaning member 48 that cleans a secondsurface of a substrate W by contacting the second surface of thesubstrate W, a second member rotation unit 98 that rotates the secondcleaning member 48, a second member drive unit 56 a that presses thesecond cleaning member 48 against the second surface of the substrate W,and a second load measurement unit 54 a that measures a pressing load ofthe second cleaning member 48. A control unit 90 controls each of apressing amount of a first cleaning member 46 by a first member driveunit 56 and a pressing amount of the second cleaning member 48 by thesecond member drive unit 56 a, on the basis of a measurement value of afirst load measurement unit 54 and a measurement value of the secondload measurement unit 54 a, so that a pressing load of the firstcleaning member 46 becomes a first setting load and a pressing load ofthe second cleaning member 48 becomes a second setting load.

In the present embodiment, each of the first cleaning member 46 and thesecond cleaning member 48 is a roll cleaning member (roll sponge)extending in a columnar shape and a long shape and made of PVA, forexample. As shown in FIG. 8 , the substrate cleaning device 16′ isfurther provided with a second member holder 44 disposed liftably underthe substrate W supported and rotated by a substrate rotation mechanism40 and a second cleaning liquid supply unit 52 for supplying a cleaningliquid to the second surface of the substrate W, and the second cleaningmember 48 is supported rotatably by the second member holder 44.

As shown in FIG. 9 , the second member rotation unit 98 is fixed to oneend side of the second member holder 44 in a longitudinal direction. Asthe second member rotation unit 98, for example, a motor is used. Thesecond member rotation unit 98 is driven, so that the second cleaningmember 48 is rotated about a center axis parallel to the surface of thesubstrate W. An arrow F2 of FIG. 8 indicates a rotation direction of thesecond cleaning member 48 by the second member rotation unit 98.

In the examples shown in FIGS. 8 and 9 , a recess 44 a is formedsubstantially at the center of the second member holder 44 along thelongitudinal direction, and the second load measurement unit 54 a isdisposed in the recess 44 a and is fixed to the second member holder 44.As the second load measurement unit 54 a, for example, a load cell isused.

As the second member drive unit 56 a, for example, an electric actuatoris used. The electric actuator may be a ball screw type electricactuator, may be a rack pinion type electric actuator, or may be adirect driven type electric actuator (linear motor).

In the example shown in the drawings, the substrate cleaning device 16′is provided with a second lift shaft 59 lifted by driving of the secondmember drive unit 56 a and extending in a vertical direction, and thesecond member holder 44 is connected to an upper end of the second liftshaft 59 via the second load measurement unit 54 a. Further, a secondtilt mechanism for tilting the second member holder 44 is providedbetween the second load measurement unit 54 a and the second memberholder 44. The second member drive unit 56 a is driven, so that thesecond member holder 44 is lifted integrally with the second lift shaft59 under the substrate W supported and rotated by the substrate rotationmechanism 40.

The control unit 90 has a second programmable logic controller (PLC)that receives an output signal of the second load measurement unit 54 aand a second motor controller that supplies electric pulses of apredetermined number of pulses to the second member drive unit 56 a,according to an instruction from the second PLC. Further, in the controlunit 90, a target value of the pressing load of the second cleaningmember 48 is stored in advance as a “second setting load”, on the basisof an input from a user to a control panel 30.

By adjusting the number of pulses of the electric pulses supplied fromthe control unit 90 to the second member drive unit 56 a, a movementamount (a pressing amount when the second cleaning member 48 contactsthe second surface of the substrate W) of the second member holder 44 inthe vertical direction can be adjusted with high accuracy.

The second member holder 44 is connected to the upper end of the secondlift shaft 59 via the second load measurement unit 54 a. In a statewhere the second cleaning member 48 does not contact the substrate W, aweight of the second member holder 44 is measured as a compressive loadby the second load measurement unit 54 a. At the time of cleaning thesubstrate W, if the second member holder 44 is moved upward by thesecond member drive unit 56 a and the second cleaning member 48 contactsthe substrate W, the compressive load applied to the second loadmeasurement unit 54 a increases according to a deformation amount of thesecond cleaning member 48 and an increased amount of the compressiveload is matched with the pressing load applied to the substrate W by thesecond cleaning member 48.

Thereby, the pressing load applied to the substrate W by the secondcleaning member 48 at the time of cleaning the substrate W is measuredby the second load measurement unit 54 a by the increased compressiveload. The control unit 90 calculates a necessary movement amount of thesecond cleaning member 48, on the basis of a measurement value of thesecond load measurement unit 54 a, so that the pressing load of thesecond cleaning member 48 becomes the second setting load, and suppliesthe electric pulses of the number of pulses corresponding to thecalculated movement amount to the second member drive unit 56 a. As aresult, the pressing amount of the second cleaning member 48 by thesecond member drive unit 56 a is adjusted, and the pressing load for thesubstrate W is adjusted according to the deformation amount of thesecond cleaning member 48.

In the present embodiment, the control unit 90 is configured to executea first step of controlling the first member drive unit 56 and thesecond member drive unit 56 a so that the first cleaning member 46 movesat a first movement speed V1 from a first initial position separatedfrom the first surface of the substrate W by a first distance D1 to afirst proximity position separated from the first surface by a thirddistance D3 and the second cleaning member 48 moves at a second movementspeed V2 from a second initial position separated from the secondsurface of the substrate W by a second distance D2 shorter than thefirst distance D1 to a second proximity position separated from thesecond surface by the third distance D3, by referring to FIGS. 12A and12B, before cleaning the substrate W.

Further, the control unit 90 is configured to execute a second step ofcontrolling the first member drive unit 56 and the second member driveunit 56 a so that the first cleaning member 46 and the second cleaningmember 48 simultaneously start moving at a third movement speed V3 lowerthan the first movement speed V1 and simultaneously contact the firstsurface and the second surface of the substrate W, respectively, byreferring to FIGS. 12B and 12C, after the first step. By moving thefirst cleaning member 46 and the second cleaning member 48 respectivelydisposed at the first proximity position and the second proximityposition having the same distances from the substrate W, symmetricallywith respect to the substrate W, and simultaneously contacting the firstcleaning member 46 and the second cleaning member 48 with the substrateW, it is possible to simultaneously and accurately position the firstcleaning member 46 and the second cleaning member 48 on the surfaces ofthe substrate W.

Further, the control unit 90 is configured to determine the secondmovement speed V2 of the second cleaning member 48 by the second memberdrive unit 56 a, on the basis of the first movement speed V1 of thefirst cleaning member 46 by the first member drive unit 56, so that thefirst cleaning member 46 disposed at the first initial position and thesecond cleaning member 48 disposed at the second initial positionsimultaneously start the moving and the second cleaning member 48reaches the second proximity position at timing identical to timing whenthe first cleaning member 46 reaches the first proximity position,before the first step. Specifically, for example, the control unit 90determines the second movement speed V2 of the second cleaning member 48by the second member drive unit 56 a by a calculation formula of V2 = V1× (D2 -D3)/(D1 - D3). By determining the second movement speed V2 of thesecond cleaning member 48 disposed at the second initial positionrelatively close to the substrate W, on the basis of the first movementspeed V1 of the first cleaning member 46 disposed at the first initialposition relatively far from the substrate W, it is possible to shortena time required for causing the first cleaning member 46 and the secondcleaning member 48 to reach the first proximity position and the secondproximity position, respectively.

Next, an example of a substrate cleaning method by the substratecleaning device 16′ having the above configuration will be described.FIG. 10 is a flowchart illustrating an example of the substrate cleaningmethod. FIG. 11 is a flowchart illustrating a step of contacting thefirst cleaning member 46 and the second cleaning member 48 with thesubstrate W.

As shown in FIG. 10 , first, if the user inputs the first setting loadand the second setting load via the control panel 30, the control unit90 calculates each of the pressing amounts of the first cleaning member46 and the second cleaning member 48 corresponding to the input settingloads (step S110).

Next, the control unit 90 supplies electric pulses of a predeterminednumber of pulses to the first member drive unit 56, moves downward thefirst cleaning member 46 by driving of the first member drive unit 56,and contacts the first cleaning member 46 with the first surface of thesubstrate W, and the control unit 90 supplies electric pulses of apredetermined number of pulses to the second member drive unit 56 a,moves upward the second cleaning member 48 by driving of the secondmember drive unit 56 a, and contacts the second cleaning member 48 withthe second surface of the substrate W (step S120).

Specifically, for example, as shown in FIG. 11 , the control unit 90determines the second movement speed V2 of the second cleaning member 48by the second member drive unit 56 a, on the basis of the first movementspeed V1 of the first cleaning member 46 by the first member drive unit56 (step S121), so that the first cleaning member 46 disposed at thefirst initial position and the second cleaning member 48 disposed at thesecond initial position simultaneously start the moving (refer to FIG.12A) and the second cleaning member 48 reaches the second proximityposition at timing identical to timing when the first cleaning member 46reaches the first proximity position (refer to FIG. 12B).

Next, referring to FIGS. 12A and 12B, the control unit 90 controls eachof the first member drive unit 56 and the second member drive unit 56 a,moves the first cleaning member 46 at the first movement speed V1 (forexample, a maximum speed by the first member drive unit 56) from thefirst initial position to the first proximity position, and moves thesecond cleaning member 48 at the second movement speed V2 determined instep S121 from the second initial position to the second proximityposition (step S122). As a result, it is possible to shorten a timerequired for causing the first cleaning member 46 and the secondcleaning member 48 to reach the first proximity position and the secondproximity position, respectively.

Next, referring to FIGS. 12B and 12C, the control unit 90 controls eachof the first member drive unit 56 and the second member drive unit 56 a,simultaneously starts moving the first cleaning member 46 and the secondcleaning member 48 at the third movement speed V3 lower than the firstmovement speed V1, and simultaneously contacts the first cleaning member46 and the second cleaning member 48 with the first surface and thesecond surface of the substrate W, respectively (step S123). As aresult, it is possible to simultaneously and accurately position thefirst cleaning member 46 and the second cleaning member 48 on thesurfaces of the substrate W.

At this time, the first cleaning member 46 only contacts the firstsurface of the substrate W, the deformation amount of the first cleaningmember 46 is zero, and the pressing load of the first cleaning member 46for the substrate W is also zero. Similarly, the second cleaning member48 only contacts the second surface of the substrate W, the deformationamount of the second cleaning member 48 is zero, and the pressing loadof the second cleaning member 48 for the substrate W is also zero.

Next, the control unit 90 supplies the electric pulses of the number ofpulses according to the pressing amounts calculated in step S110 to thefirst member drive unit 56 and the second member drive unit 56 a andpresses the first cleaning member 46 and the second cleaning member 48against the first surface and the second surface of the substrate W bythe calculated pressing amounts by the first member drive unit 56 andthe second member drive unit 56 a (step S130).

The first load measurement unit 54 and the second load measurement unit54 a respectively measure the pressing loads of the first cleaningmember 46 and the second cleaning member 48 for the substrate W (stepS140).

Then, the control unit 90 controls the pressing amounts of the firstcleaning member 46 and the second cleaning member 48 by the first memberdrive unit 56 and the second member drive unit 56 a by closed loopcontrol, on the basis of the measurement values of the first loadmeasurement unit 54 and the second load measurement unit 54 a, so thatthe pressing load of the first cleaning member 46 becomes the firstsetting load input by the user and the pressing load of the secondcleaning member 48 becomes the second setting load input by the user(step S150). As a result, the pressing loads of the first cleaningmember 46 and the second cleaning member 48 are adjusted with highaccuracy so as to have substantially the same values as the first andsecond setting loads input by the user.

According to the present embodiment described above, referring to FIGS.12A and 12B, the second movement speed of the second cleaning member 48disposed at the second initial position relatively close to thesubstrate W is determined on the basis of the first movement speed ofthe first cleaning member 46 disposed at the first initial positionrelatively far from the substrate W. Therefore, it is possible toshorten a time required for causing the first cleaning member 46 and thesecond cleaning member 48 to reach the first proximity position and thesecond proximity position, respectively. As a result, it is possible toincrease the number of substrates processed per unit time (wph; waferper hour).

Further, according to the present embodiment, referring to FIGS. 12B and12C, the first cleaning member 46 and the second cleaning member 48respectively disposed at the first proximity position and the secondproximity position having the same distances from the substrate W aremoved symmetrically with respect to the substrate W and the firstcleaning member 46 and the second cleaning member 48 are simultaneouslycontacted with the substrate W. Therefore, it is possible tosimultaneously and accurately position the first cleaning member 46 andthe second cleaning member 48 on the surfaces of the substrate W. As aresult, subsequent pressing amount control can be performed with highaccuracy, and accuracy of the pressing load can be improved.

Further, according to the present embodiment, since each of the firstmember drive unit 56 and the second member drive unit 56 a is theelectric actuator, the pressing amounts of the first cleaning member 46and the second cleaning member 48 can be controlled with high accuracy,as compared with the case where air cylinders are adopted as the firstmember drive unit 56 and the second member drive unit 56 a. As a result,accuracy of the pressing load can be further improved.

Although the embodiments and the modifications of the present technologyare described by the examples, a range of the present technology is notlimited thereto, and changes and modifications according to objects canbe made within a range described in claims. Further, the embodiments andthe modifications can be appropriately combined within a range in whichprocessing contents are not contradicted.

What is claimed is:
 1. A substrate cleaning device comprising: a firstcleaning member configured to clean a first surface of a substrate bycontacting the first surface of the substrate; a first member rotationunit configured to rotate the first cleaning member; a first memberdrive unit configured to press the first cleaning member against thefirst surface of the substrate; a first load measurement unit configuredto measure a pressing load of the first cleaning member; a secondcleaning member configured to clean a second surface of the substrate bycontacting the second surface of the substrate; a second member rotationunit configured to rotate the second cleaning member; a second memberdrive unit configured to press the second cleaning member against thesecond surface of the substrate; a second load measurement unitconfigured to measure a pressing load of the second cleaning member; anda control unit configured to control a pressing amount of the firstcleaning member by the first member drive unit and a pressing amount ofthe second cleaning member by the second member drive unit, on the basisof a measurement value of the first load measurement unit and ameasurement value of the second load measurement unit, so that thepressing load of the first cleaning member becomes a first setting loadand the pressing load of the second cleaning member becomes a secondsetting load, wherein the control unit is configured to execute a firststep of controlling the first member drive unit and the second memberdrive unit so that the first cleaning member moves at a first movementspeed from a first initial position separated from the first surface ofthe substrate by a first distance to a first proximity positionseparated from the first surface of the substrate by a third distanceand the second cleaning member moves at a second movement speed from asecond initial position separated from the second surface of thesubstrate by a second distance shorter than the first distance to asecond proximity position separated from the second surface of thesubstrate by the third distance and a second step of controlling thefirst member drive unit and the second member drive unit so that thefirst cleaning member and the second cleaning member simultaneouslystart moving at a third movement speed lower than the first movementspeed and simultaneously contact the first surface of the substrate andthe second surface of the substrate, respectively, and the control unitis configured to determine, before the first step, the second movementspeed of the second cleaning member by the second member drive unit, onthe basis of the first movement speed of the first cleaning member bythe first member drive unit, so that the first cleaning member disposedat the first initial position and the second cleaning member disposed atthe second initial position simultaneously start the moving and thesecond cleaning member reaches the second proximity position at timingidentical to timing when the first cleaning member reaches the firstproximity position.
 2. The substrate cleaning device according to claim1, wherein each of the first cleaning member and the second cleaningmember is a roll cleaning member.
 3. The substrate cleaning deviceaccording to claim 1, wherein each of the first member drive unit andthe second member drive unit is an electric actuator.
 4. A substrateprocessing apparatus comprising the substrate cleaning device accordingto claim 1.